A Wireless Local Area Networks(WLAN) Security Mechanism Based On Digital Signature

WLAN (Wireless Local Area Networks) is a computer area network which use wireless communication technology. With the popularization of the wireless communication technology, the technique of WLAN get great development. Which makes us get away from the astriction of the numerous and jumbled network line, and gives us great convenience. However, WLAN's carrier is the public electromagnetic wave, so they are harder to defending the eavesdropping and unauthorized acess. The WLAN's security is now seriously slowing down the development the WLAN. Manufacturers have published many WLAN security machanisms to solve the security problem. These machanisms guarantee the security of WLAN in some extend. But they also need to be updated and improved because of their bugs and weaknessesFor some main factor of the WLAN's security, a new WLAN security mechanism based on digital signature is presented in this paper. This mechanism aims at the WLAN's three threats: wireless eavesdropping, counterfeiting identity and modifying data. This mechanism included two modes: one was certification but non-encryption mode .In this mode, after connecting successfully between TER(Terminal) and AP(Access Point), they started non-encryption communication; the other one was certification and encryption mode, in this case, they started encryption communication.The mechanism based on RSA public key System and MD5 hash function, and also use the certificate to authenticate the AP and TER in WLAN. Defining a entity which named CA(Certificate Authority). This entity manage the certificate which used for the information exchange (including create, issue, revoke the certificate).The whole mechanism provided many services such as certification and authentication, integrity, availability, non-repudiation, confidentiality and so on. Algorithm is mature, credible and easy to implement. At the last part of this paper, the mechanism and the algorithm's security performance was evaluated, also the implement schemes under some conditions was presented.